She looks sweet grooming her chick, but don't mess with mom's nest: Ural owls are aggressively territorial. "I've made an 'agreement' with the females that the price to band and measure one nestling is six hard punches on the head," says Finnish ornithologist Pertti Saurola.

A male (at right) delivers a freshly caught rodent to his mate, and she will bring it back to their nearby nest. Since unattended chicks could be vulnerable to hawks and other hungry birds, the male does most of the hunting during the breeding season.